Security readout for executives and security teams
Plain-English summary
This flaw affects Atlassian Connect apps built with vulnerable Atlassian Connect Spring Boot versions. The framework could accept a weaker token type on lifecycle endpoints, allowing an authenticated attacker to trigger app re-installation events. That can affect trust, configuration, and app state for Jira or Confluence integrations.
Executive priority
Treat this as urgent for Atlassian Connect app owners, especially where apps are internet-facing or business-critical. Prioritize dependency upgrades and evidence review before assuming compromise.
Technical view
ACSB incorrectly accepted context JWTs on lifecycle endpoints where server-to-server JWTs were required. A low-privileged network attacker could send authenticated re-installation lifecycle events to an app. Affected ranges are ACSB 1.1.0 before 2.1.3 and 2.1.4 before 2.1.5. CVSS is 9.1, CWE-287.
Likely exposure
Exposure is limited to organizations running Atlassian Connect apps that use vulnerable Atlassian Connect Spring Boot dependency versions. The risk is higher for externally reachable app backends handling lifecycle endpoints.
Exploitation context
The CVE indicates network reachability, low required privileges, no user interaction, and changed scope. The provided data does not show CISA KEV listing or confirmed active exploitation.
Researcher notes
Key validation should focus on dependency version, lifecycle endpoint JWT handling, and historical install events. The supplied sources identify the flaw class and affected ranges but do not provide evidence of active exploitation.
Mitigation direction
- Upgrade ACSB outside the affected ranges, following Atlassian guidance.
- Identify all Atlassian Connect apps using ACSB dependencies.
- Review lifecycle endpoint authentication assumptions and tests.
- Investigate unexpected app re-installation lifecycle events.
- Check Atlassian advisory updates for product-specific guidance.
Validation and detection
- Inventory package manifests for vulnerable ACSB versions.
- Confirm lifecycle endpoints require server-to-server JWTs only.
- Review logs for unusual installation or re-installation events.
- Verify upgraded apps pass unit and integration authentication tests.
- Confirm deployed artifacts match reviewed dependency versions.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-287: Credential and account abuse lookup
Authentication and credential weaknesses can make valid-account abuse and credential telemetry useful review starting points. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-26077 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L3.15.3Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.1CriticalVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L
Source materials
- CVE List V5 sourceCVE List V5
- https://community.developer.atlassian.com/t/action-required-atlassian-connect-vulnerability-allows-bypass-of-app-qsh-verification-via-context-jwts/47072CVE reference · x_refsource_MISC
- https://confluence.atlassian.com/pages/viewpage.action?pageId=1063555147CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Authentication
Improper Authentication represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.